Novag Novag-2k User manual

Service Manual

2K Pumping System

Non-Heated

Issue 1.6 23/03/20

Ref. NR-00026-ENG

Before installing the unit and starting it up, read all the technical and

safety documentation included in this manual carefully. Pay special

attention to the information to know and understand the operation and the

conditions of use of the unit. All of the information is aimed at enhancing

User Safety and avoiding possible breakdowns derived from the incorrect

use of the unit.

novaG –2K

Service Manual

2/23 Issue 1.6 Ref. NR-00026-ENG

http://www.novag.eu/

HI-TECH SPRAY EQUIPMENT, S. A. (hereinafter “HI-TECH”) provides this LIMITED WARRANTY (hereinafter

“Warranty”) to the original purchaser (hereinafter “Customer”) covering this equipment and the original HI-TECH

manufactured accessories delivered with the equipment (hereinafter “Product”) against defects in material or

workmanship of the Product (hereinafter “Defect” or “Defective”) for a period of two (2) years from the date of first

purchase as shown on the original HI-TECH invoice (hereinafter “Warranty Period”).

If during the Warranty Period under normal use, the Product is suspected by Customer to be Defective in material or

workmanship, it is Customer’s responsibility to contact HI-TECH and return the Product to HI-TECH as directed by HI-

TECH, freight prepaid. If HI-TECH determines that the Product is Defective and that such Defect is covered by this

Warranty, HI-TECH will credit Customer for the reasonable freight charges incurred by Customer in returning the

Defective Product to HI-TECH, and HI-TECH (or its authorized agent) will, at HI-TECH’s option, repair or replace the

Product, subject to the following:

Original Invoice: The original invoice must be kept as proof of the date of first sale and the Product serial number. The

Warranty does not cover any Product if the Original Invoice appears to have been modified or altered, or when the serial

number on the Product appears to have been altered or defaced.

Product Maintenance: It is the Customer’s responsibility to maintain the Product properly. See your maintenance

schedule and owner’s manual for details. The Warranty does not cover an improperly maintained Product.

Non-HI-TECH Components and Accessories: Non-HI-TECH manufactured components and accessories that are used

in the operation of the Product are not covered by this Warranty. Such components and accessories shall be subject to

the warranty offered to the Customer, if any, by the original manufacturer of such component or accessory.

Other Warranty Exclusions: The Warranty does not cover any Product that HI-TECH determines has been damaged or

fails to operate properly due to misuse, negligence, abuse, carelessness, neglect, or accident. By way of example only,

this includes:

•Normal wear and tear.

•Improper or unauthorized installation, repair, alteration, adjustment or modification of the Product.

•Use of heating devices, pumping equipment, dispensers, or other parts or accessories with the Product that

have not been approved or manufactured by HI-TECH.

•Failure to follow the operating instructions and recommendations provided by HI-TECH.

•Cosmetic damage.

•Fire, flood, “acts of God,” or other contingencies beyond the control of HI-TECH.

THE WARRANTY DESCRIBED HEREIN IS THE EXCLUSIVE REMEDY FOR THE CUSTOMER AND IS IN LIEU OF ALL OTHER

WARRANTIES, EXPRESS, IMPLIED, STATUTORY OR OTHERWISE, AND THE IMPLIED WARRANTIES OF MERCHANTABILITY

AND FITNESS FOR A PARTICULAR PURPOSE AND ALL OTHER WARRANTIES ARE HEREBY DISCLAIMED. TO THE FULLEST

EXTENT PERMITTED BY LAW, HI-TECH SHALL NOT BE RESPONSIBLE, WHETHER BASED IN CONTRACT, TORT (INCLUDING,

WITHOUT LIMITATION, NEGLIGENCE), WARRANTY OR ANY OTHER LEGAL OR EQUITABLE GROUNDS, FOR ANY

CONSEQUENTIAL, INDIRECT, INCIDENTAL, LOST PROFITS, SPECIAL, PUNITIVE OR EXEMPLARY DAMAGES, WHETHER TO

PERSON OR PROPERTY, ARISING FROM OR RELATING TO THE PRODUCT, EVEN IF HI-TECH HAS BEEN ADVISED OF THE

POSSIBILITY OF SUCH LOSSES OR DAMAGES.

Non-Warranty Service by HI-TECH: If HI-TECH determines that the suspected Defect of the Product is not covered by

this Warranty, disposition of the Product will be made pursuant to the terms and conditions of HI-TECH’s written

estimate on a time and materials basis.

Continuing Warranty for Products Repaired or Replaced under Warranty: Following the repair or replacement of a

Product covered by this Warranty, such Product will continue to be subject to the original Warranty for the remainder of

original Warranty Period or for three (3) months from the repair or replacement date, whichever is longer.No Rights

Implied: Nothing in the sale, lease or rental of any Product by HI-TECH shall be construed to grant any right, interest or

license in or under any patent, trademark, copyright, trade secret or other proprietary right or material owned by anyone;

nor does HI-TECH encourage the infringement of same.

Exclusive Warranty: This writing is the final, complete, and exclusive expression of the Warranty covering the Product.

Any statements made by HI-TECH, its employees or agents that differ from the terms of this Warranty shall have no

effect. It is expressly understood that Customer’s acceptance of this Warranty, by performance or otherwise, is upon

and subject solely to the terms and conditions hereof, and any additional or different terms and conditions proposed or

expressed by Customer or anyone, whether in writing or otherwise, are null and void unless specifically agreed to in

writing by an Officer of HI-TECH.

WARRANTY

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Service Manual

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All information provided in this Service Manual is assumed to be correct; although this does not

constitute any implicit or explicit liability or guarantee. HI-TECH reserves the right at any time

and without prior warning to make all improvements and modifications necessary to this Service

Manual, in order to rectify any possible typographical errors, supplement the information

contained or insert changes predicated by the performance or use of the unit.

This chapter contains information on the safety, handling and use of the novaG-2K series

proportioning unit.

Before installing the unit and starting it up, read all the technical and

safety documentation included in this manual carefully. Pay special

attention to the information to know and understand the operation and the

conditions of use of the unit. All of the information is aimed at enhancing

User Safety and avoiding possible breakdowns derived from the incorrect

use of the unit.

WARNING! establishes information to alert on a situation that might cause serious

injuries if the instructions are not followed.

CAUTION! establishes information that indicates how to avoid damage to the unit or

how to avoid a situation that could cause minor injuries.

NOTE: is relevant information on a procedure being carried out.

Careful study of this manual will enable the operator to know the characteristics of the unit and

the operating procedures. By following the instructions and recommendations contained herein,

you will reduce the potential risk of accidents in the installation, use or maintenance of the unit;

you will provide a better opportunity for incident-free operation for a longer time, greater output

and the possibility of detecting and resolving problems fast and simply.

Keep this Service Manual for future consultation of useful information at all times. If you lose

this manual, ask for a new copy from your NOVAG local distributor or directly contact NOVAG

SPRAY EQUIPMENT, S.A.

WARNING! The design of the novaG-2K series proportioning unit does not allow its

use in potentially explosive atmospheres or to exceed the pressure and temperature

limits described in the technical specifications of this manual.

SAFETY AND HANDLING

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When working with the unit, it is recommended that the operator wear suitable clothing and

elements of personal protection, including, without limitation, gloves, protective goggles, safety

footwear and face masks. Use breathing equipment when working with the machine in

enclosed spaces or in areas with insufficient ventilation. The introduction and follow-up of

safety measures must not be limited to those described in this manual. Before starting up the

machine, a comprehensive analysis must be made of the risks derived from the products to be

dispensed, the type of application and the working environment.

To prevent all possible bodily harm caused by incorrect handling of the

raw materials and solvents used in the process, carefully read the safety

information provided by your supplier.

Deal with the waste caused according to current regulations.

Disconnect the unit from the pneumatic supply before carrying out any

operation on the Unit.

To avoid damage caused by the impact of pressurized fluids, do not open

any connection or perform maintenance work on components subject to

pressure until the pressure has been completely eliminated.

Use suitable protection when operating, maintaining or remaining in the

operating area of the unit. This includes, but is not limited to, the use of

masks, protective goggles, gloves, shoes and safety clothing.

To prevent serious harm by crushing or loss of limbs, do not work with

the unit without the safety guards installed on all moving parts. Make

sure that all of the safety protections are correctly reinstalled after all

repair or maintenance work is completed.

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Service Manual

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The novaG-2K proportioning unit has been designed and built for the application of Polyureas,

chemical systems for polyurethane foaming, and some two-component Epoxy systems.

Its reduced size allows easy transport to site. Its easy operation (simply turn the valve switch)

reverts into time saving during set up and application.

Proportioning Pumps

Comprises two positive displacement piston pumps, driven by a pneumatic motor. The system

includes two pressure regulators that allow the working pressures to be equalized in the two

directions of pump movement, compensating for the imbalance of pressure caused by the

difference between the upper and the lower side of the air motor, and the effect of the additional

pressure of the transfer pumps.

CHARACTERISTICS

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Electrical

Main Voltage: ________________________________________________________________ -

Frecuency: __________________________________________________________________ -

Electrical Consumption: ________________________________________________________ -

Heater Power:________________________________________________________________ -

Transformer Active Power:______________________________________________________ -

Total Active Power: ___________________________________________________________ -

Mechanical

Maximum Working Pressure (air supply 9 bar):_________________________200 bar (20 MPa)

Maximum Production Ratio 1:1:____________________________________________ 4 kg/min

Minimum Production: ____________________________________________________ 1 kg/min

Maximum Hose Length: _____________________________________________________ 93 m

Recommended Compressor: ______________________________________ 7,5 HP one-phase

Approximate weight:________________________________________________________77 kg

Dimensions: ___________________________________ H: 1035 mm / W: 610 mm / L: 640 mm

TECHNICAL SPECIFICATIONS NOVAG-2K

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Figure 1. General Description novaG-2K

GENERAL DESCRIPTION

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1. Pneumatic Control

Controls and regulates the operation of the unit.

2. Isocyanate Proportioning Pump

Meters the Isocyanate.

3. Polyol Proportioning Pump

Meters the Polyol.

4. Cycle Counter

Counts cycles. It is increasing and can ve reset by pressing the RESET key which is located at

left of the numeric counter.

5. Pressure Regulators

Using the two air pressure regulators, select the pressure for the down stroke and the up stroke

of the pneumatic cylinder.

6. Auxiliary Air Connection

Air connection for the Gun.

7. Supply Air Valve

Open & Close the supply air to pneumatic circuit to Unit. The valve has an exhaust in close

position for depresurized the Unit.

8. Isocyanate Pressure Gage

Indicates the pressure in the Isocyanate system.

9. Polyol Pressure Gage

Indicates the pressure in the Polyol system.

10. Isocyanate Recirculation valve

Open & Close the recirculation from ISO Pump to external ISO tank.

11. Polyol Recirculation valve

Open & Close the recirculation from POL Pump to external POL tank.

12. Retract Valve

Sets the piston rod of the Isocyanate proportioning pump to the retract position and prevents the

crystallization of Isocyanate on the piston rod. Close the RETRACT valve every time the unit is

stopped by the operator.

13. Isocyanate Inlet Selector

3-way valve that determine the origin of inlet ISO product.

14. Polyol Inlet Selector

3-way valve that determine the origin of inlet POL product.

15. Isocyanate tank (internal)

30 Lt ISO tank, included on the frame of Unit.

16. Polyol tank (internal)

30 Lt POL tank, included on the frame of Unit.

17. Supply Hoses from external tank

Supply hoses product from esternal tanks.

18. Recirculation Hoses

Recirculation hoses from pumps to external tanks.

19. Isocyanate Inlet Filter

Avoids the penetration of solid particles inside the Isocyanate pump of the unit.

20. Polyol Inlet Filter

Avoids the penetration of solid particles inside the Polyol pump of the unit.

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CAUTION! Use suitable protection and follow the recommendations in the safety

information provided by product suppliers when installing or working with the unit.

Follow the recommended procedure in the indicated order to install

the unit:

a) Fill the Isocyanate pump lubricating cup with DOTP

plasticizer.

b) Connect the pressure hose of each product to the outlet of

the respective pumps (the Isocyanate hose to the Isocyanate

pump and the Polyol hose to the Polyol pump).

NOTE: The product hoses have been identified with red (Isocyanate) and blue (Polyol),

enabling them to be rapidly distinguished. To avoid errors in connecting the coupling

connectors of the Isocyanate and Polyol hoses, the connectors are of different sizes to

make it impossible for connections to be swapped.

Figure 2. Method of union of the Hoses

WARNING! To join the hoses together or to connect them to the heaters or the gun,

use two spanners to hold the parts to be joined (1) and a third spanner to tighten or

loosen the connecting nut (2) as shown in the illustrations in Figure 2. The connections

must be tightened to a torque of 20 Nm.

The hoses receive vacuum drying treatment and are supplied interconnected at the ends to

prevent them from absorbing moisture. Do not separate them until they are going to be

installed in the unit.

INSTALLATION

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NB: Assure the proper mechanical connection of the hoses to avoid possible product

leakage.

a) Connect the air hoses.

b) Connect the hoses to the connectors of the coupling block of the gun, making sure that

the manual valves are closed.

c) Proceed to install the supply hoses paying special attention to connect each hose to

“its” product, as changing the hoses would cause a reaction in the products inside

them and make them useless. Identify each hose with a tape of color with the tipical

product definition (blue for the Polyol and red for the Isocyanate) is a good method for

avoiding errors in connection.

Do the following steps to install the hoses:

a) Make sure that the inlet valves of the products to the unit are closed.

b) Connect one end of the Polyol hose to the Polyol valve and the other end in to the

external POL tank.

c) Connect one end of the Isocyanate hose to the Isocyanate valve and the other end in to

the external ISO tank.

Before using the unit, the retained air and the residual oil from

the operating tests made in the factory must be eliminated. To

purge the whole circuit, proceed as follows:

a) Open the inlet ball valves. Make sure there are no

leaks.

b) Keep the coupling block with each product’s outlet in

separate vessels and open the valves of each product.

c) Turn the pneumatic pressure regulator anti-clockwise

until the end.

d) Turn the RETRATC valve.

e) Turn the GENERAL valve, the proportioning pumps will

move upwards due to the aspiration of the same.

f) If necessary, increase the pneumatic pressure by

turning the regulator clockwise until the product pumps

begin to move slowly.

g) Allow the materials to come out of the recirculation hose

until the residual oil and the air bubbling has

disappeared completely.

h) Close the manual valves of each product and remove

any remains of product in the coupling block.

i) Slowly increase the pneumatic pressure to check for

product leaks in the hose connections. Re-tighten and

tape-cover the union connectors to protect them from

possible damage.

j) Turn the RETRATC valve.

k) Turn the GENERAL valve

l) Mount the gun on the coupling block.

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Follow the recommended procedure in the indicated order.

PRECAUTION! The start-up procedures assume that all of the necessary adjustments

have been correctly performed.

a) Check the state of the DOTP plasticizer in the Isocyanate pump lubrication cup.

Change the oil if you see changes in the color or signs of solidification and retighten the

packing nut to ensure the seal.

b) Check the inlet filters of the products. Clean them if necessary.

c) Open the inlet ball valves of the products to the unit.

d) Turn the general pneumatic valve ON.

e) Turn the RETRATC valve (in vertical position), the proportioning pumps will move.

f) Using the pneumatic pressure regulators, choose the pressure for the decreasing cycle

of the proportioning pumps first, and then adjust the pressure for the increasing cycle. A

little pressure imbalance between the increasing and the decreasing cycle of the pump

will occur. This is due to the difference between the upper and the lower side of the air

motor. In order to balance the pressures, the value of the pneumatic pressure in the

increasing cycle must be slightly lower (between 0.2 and 0.4 kg/cm2) than the set value

of the pneumatic pressure of the decreasing cycle of the pumps.

The pressures must be practically the same and remain constant.

Should the pressures fluctuate on each stroke, consult the fault section before

continuing.

g) Connect the air supply to the gun; open the manual valves of each product; make a test

projection and check the pressures on the product gauges. If the projection test is

correct and the pressures remain equal, proceed with the application.

START-UP PROCEDURES

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Follow the recommended procedure in the indicated order:

a) Turn the RETRATC valve.

b) Use the gun to project into a waste container until the Isocyanate proportioning pump is

in the retract position and the pressure begins to fall.

CAUTION! To avoid possible product leakage and early failure of the pump seals, the

pressure must not be reduced to zero. It is recommended to keep the system with a

minimum pressure of 30 bar (400 psi) to extend the life of the seals.

c) Turn the air supply valve in OFF position (transversal respect to the flow direction).

d) Close the manual valves at the inlet of the filters.

e) Roll the hoses.

f) Close the manual valves on the coupling block and dismantle the gun to perform the

corresponding maintenance.

DAILY SHUTDOWN

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To avoid possible contamination, the circuits of the unit must be flushed clean (pumps and

hoses) whenever applications have to be made that require a change of components.

Follow the recommended procedures in the order indicated to perform the cleaning:

a) Place two drums of DOTP cleaning agent close to the machine. If you use external

product tanks, you can use the 30 Lt tanks attached to the frame for this purpose.

b) Dismantle the gun and leave the coupling block connected to the hoses.

c) Remove the supply hoses of the product drums and place them in the drums of the

DOTP cleaning agent. If using the 30Lt tanks for the DOTP agent, turn the 3 way valves

at the pump inlet.

d) Place 2 separate vessels under the coupling block to gather up the products contained

inside the machine.

e) Open the manual valves on the coupling block.

f) Turn the RETRATC valve.

g) Turn the air supply valve, the proportioning pumps will move.

h) Allow the products to come out until you see that only DOTP cleaning agent comes out

free of impurities.

i) Close the valves on the coupling block and turn the air supply valve.

j) Place the hoses in the drums of the new products. If you have used the 30 Lt tanks for

the DOTP agent, replace the 3 way valves in the feed position from the external tanks.

k) Place two separate vessels under the coupling block to collect the DOTP cleaning

agent.

l) Open the valves on the coupling block and turn the air supply valve, the proportioning

pumps will move.

m) Allow the DOTP cleaning agent to come out until you see that only the new products

come out.

n) When the products come out without the contamination produced by the effect of the

DOTP cleaning agent, the cleaning process is complete and you can proceed as

normal.

CLEANING

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When you plan to shut down the machine for more than FOUR weeks, the products contained

in the machine must be replaced by DOTP plasticizing agent.

Follow the recommended procedures in the order indicated:

a) Turn the air supply valve OFF (transversal to the flow air direction).

b) Place two drums of DOTP cleaning agent close to the machine. If you use external

product tanks, you can use the 30 Lt tanks attached to the frame for this purpose.

c) Dismantle the gun and leave the coupling block connected to the hoses.

d) Remove the supply hoses of the product drums and place them in the drums of the

DOTP cleaning agent. If using the 30Lt tanks for the DOTP agent, turn the 3 way valves

at the pump inlet.

e) Place 2 separate vessels under the coupling block to gather up the products contained

inside the machine.

f) Open the manual valves on the coupling block and turn the air supply valve, the

proportioning pumps will move.

g) Allow the products to come out until you see that only DOTP cleaning agent comes out

free of impurities.

h) Turn the RETRATC and the air supply valve, disconnect the supply system and the

process is finished. The proportioning pumps and the hoses must be full of DOTP

plasticizing oil. Never leave the machine or the hoses empty of product or DOTP

plasticizing oil.

NOTE: Never use liquids not recommended or not approved by HI-TECH. Never use

approved liquids that have been contaminated with water or ISO/POL. If you are not sure

in the quality of the liquid you are going to use we strongly recommend that you check

the machine 2-3 times every 2 weeks after you have filled it by recirculating through

hoses (see p. 13) with fresh plasticizer unless you make sure the liquid that comes out is

completely pure and clean.

LONG TERM SHUTDOWN PROCEDURES

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The novaG-2K unit has been designed and built to withstand severe working conditions with a

high degree of reliability, provided it is used suitably. This chapter contains information on

possible faults that may prevent the continuation of work with the unit. The information provided

must serve as guideline to detect and resolve the large majority of the problems before calling

for the assistance of the authorized distributor or HI-TECH technical service. In any case, feel

free to contact the technical assistance service of HI-TECH SPRAY EQUIPMENT, S.A. where a

qualified technician will advise you on whatever you may need.

NOTE: All repairs performed by unqualified personnel or the use of spares other than

originals may cause damage to the unit and put the operator at risk.

To prevent possible bodily harm caused by incorrect handling of the raw

materials and solvents used in the process, carefully read the safety

information provided by your supplier.

Deal with the waste caused according to current regulations.

Disconnect the unit from the pneumatic supply before carrying out any

operation of mantinence.

To avoid damage caused by the impact of pressurized fluids, do not open

any connection or perform maintenance work on components subject to

pressure until the pressures have been completely eliminated.

Use suitable protection when operating, maintaining or remaining in the

operating area of the unit. This includes, but is not limited to, the use of

face masks, protective goggles, gloves, shoes and safety clothing.

To prevent serious harm by crushing or loss of limbs, do not work with

the unit without the safety duly installed on all moving parts. Make sure

that all of the safety protections are correctly fitted after all repair or

maintenance work.

TROUBLESHOOTING

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Proportioning Pumps

WARNING! Before resolving any kind of defect, make sure all of the pushbuttons are

off, that the general switch is in shutdown position and that the unit is disconnected from

the pneumatic supply source.

PROBLEMS SOLUTIONS

The pumps fail to maintain the pressure when the unit is shut down.

There are pressure differences between the proportioning pumps.

1-2-3

There is cavitation in the proportioning pump.

1-2-3

The proportioning pumps do not change direction.

The proportioning pumps fail to move and the direction indicator lights are

out.

The movement of the proportioning pumps is erratic.

Difference of pressure or speed in the up stroke against the down stroke.

SOLUTIONS

1. Loss in the Ball Checks

Check the pressure gauges to identify which pump is not maintaining pressure. To determine

which ball valve is failing, check in which displacement direction the pump is losing pressure. If

pressure is lost in an ascending direction, check the discharge ball valve (upper valve), if

pressure is lost in a descending direction, check the aspiration ball valve (lower valve).

Proceed as follows to check the ball checks:

a) Disconnect the machine from the pneumatic supply and close all supply valves and the

supply system to the hoses products.

b) Depressurise the proportioning pump and remove the corresponding ball check.

c) The loss from the ball checks is usually caused by foreign particles that prevent the

perfect coupling of the ball in the housing at the top of the closing bushing. Clean the

ball and the seat of the bushing and make sure there are no faults from nicks, marks or

scratches to the bushing or the ball. If cleaning fails to resolve the problem or any fault

is observed, replace the bushing and the ball.

2. Unbalanced Pressures

Pressures are unbalanced when there is an obstruction in the hose or in the gun that prevents

one of the components from leaving freely through the gun chamber when it is projected, or

when a problem in the pumping system prevents one of the components reaching the gun in the

required amount.

To identify which component is relatively easy if we bear in mind that the chemical components

used in the polyurethane foaming are of a different color. By observing the color of the material

that leaves the gun, we can determine which component is missing.

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To determine if the decompensation occurs as a result of an obstruction or as a result of a

problem in the pumping system, project with the gun, observe the pressure indicated by the

manometer corresponding to the missing component and compare it with the pressure indicated

by the manometer of the other component: if the pressure of the missing component is greater,

decompensation is a consequence of an obstruction, if the pressure is lower the

decompensation is a consequence of a problem in the pumping system

3. Cavitation

Cavitation occurs when the proportioning pump requires a larger volume of material than that

supplied by the feeding system, causing the formation of a vacuum in the proportioning pump.

The causes of cavitation are the following:

a) High viscosity: the polyurethane foaming systems normally require a minimum transfer

temperature of 12º C; at lower temperatures, the product increases in viscosity, making

the pumping more difficult. When the ambient conditions prevent the products from

being maintained at a minimum temperature of 12º C auxiliary heating elements must

be used to condition the products as the minimum temperature required for the transfer.

b) The product inlet filter is obstructed (see Maintenance).

c) The inlet ball valve has leaks as a result of wear or possible faults in the ball or the

closing surface of the bushing, which means that part of the material supplied returns to

the supply tank and that the proportioning pump supplies a smaller volume of material

in the discharge cycle, causing an incorrect ratio.

4. Fault in the Direction Change Micro

The pneumatic cylinder that drives the supply pumps has two magnetic position detectors for

making the change of direction. Each detector includes an led to indicate when it is active. Any

accidental movement of the detection position will prevent the pumps from making the change

in direction, which will oblige the detector to be put back into the correct position by using the

gauge supplied with all of the accessories.

5. Rising Movement Pressure Regulator

During the up stroke, the pumps must self-aspirate the products through the feeding hoses.

Adjust the up-stroke regulator so that the pressure of the proportioning pumps is the same in

both directions.

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To achieve maximum output from the novaG-2K unit, certain daily or regular maintenance

operations are needed.

To prevent all possible body harm caused by incorrect handling of the raw